Tor Browser 16.0 lands on Firefox ESR 153: ARM64 Linux and quieter window titles
Tor Browser 16.0 arrived on October 29, 2026, and it is the project's first stable release built on Firefox ESR 153. The desktop and Android builds ship with Firefox 153.6.0esr underneath, NoScript 13.6.37.1984, tor 0.4.9.15 and Go 1.26.10, according to the Tor Project's release announcement. The version number is small; the amount of upstream Firefox that came with it is not.
A year of Firefox changes, audited one by one
Tor Browser is a patched Firefox, and every ESR transition forces the team to re-examine what Mozilla changed. For 16.0 that meant an audit of more than 270 Bugzilla issues, covering preference changes between Firefox 141 and 153 that could affect privacy or anonymity. The release notes describe the work as the annual ESR transition audit; the practical effect is that features Mozilla enabled by default get switched off or gated before users ever see them. That review is the reason a Tor Browser major release is never just a version bump. Anything that introduces a new timing source, a new identifier, or a new network call has to be found and neutralised, because the browser's threat model assumes the page and the platform may both be hostile.Native ARM64 Linux, and the end of 32-bit x86
After a year of testing, 16.0 adds native support for 64-bit ARM Linux (AArch64). That covers Raspberry Pi boards and Apple Silicon machines running Linux, both of which previously relied on emulation or the alpha channel. Users who had been running the alpha builds are advised to move to the stable channel. The same release ends 32-bit x86 Linux support, following Firefox's own decision. The numbers behind that call are modest: the project says roughly 200 update checks a day still come from 32-bit Linux, against a 2019 peak of about 4,000. Most of the remainder can move to the 64-bit build. Android x86 support was removed as well.Settings rebuilt from scratch
The most visible change is a redesign of the settings interface. The old General page is gone, its contents split across new pages for Appearance, Downloads, Tabs and browsing, Accessibility, and Languages. The Tor-specific pages for Connection and Security Level were rebuilt using Firefox's newer components, and existing preferences carry over rather than resetting. The rebuild also gave the team room to hide or warn about options that weaken protection. Settings that can make a user more fingerprintable are no longer presented as ordinary toggles. For a walkthrough of what the security levels themselves do, see our explainer on Standard, Safer and Safest.Window titles become optional
The release adds an opt-in control under Privacy and security, in a section called Protections from third-party applications. When enabled, it replaces every window title with the words Tor Browser, so other software on the machine cannot read the page you are on from the title bar or the task switcher. The underlying preferences are privacy.exposeContentTitleInWindow and privacy.exposeContentTitleInWindow.pbm, both set to false. It is off by default, and the release notes are explicit about why: the side effects on accessibility tools and custom desktop environments have not been evaluated. CyberInsider's write-up makes the same point and adds a caveat worth repeating, that hiding titles closes one channel of exposure and does not protect against software already running on the same machine. The capability was upstreamed to Firefox through the Tor Uplift project, so it is not exclusive to Tor Browser.What was switched off
Several upstream features are disabled in this build:- WebGPU, held back until it has been audited.
- WebXR, explicitly disabled.
- XSLT, disabled as of 16.0.
- IP Protection, profile backup, split view, Firefox Labs and the AI settings, all hidden.
- Google Lens, Google Ads, Play Integrity and the Mozilla VPN promotion, disabled.
Android, and what comes next
On Android the interface continues its move to Jetpack Compose and Material Design 3, with large parts of the UI updated and more to follow. The APK is also capped at 100 MB, a limit imposed by Google Play rather than chosen by the project. A redesigned circuit display is in the works. It will appear in Tor Browser Alpha first, integrating site information into the circuit panel and supporting more complex multi-path circuits, and it will mark the first time the circuit display reaches Android, where it has so far been desktop-only.Tails 7.16 ships it a day later
Tails 7.16, released October 30, bundles Tor Browser 16.0 and the Tor client 0.4.9.15, and inherits the redesigned settings. The release also fixes OpenPGP support in Thunderbird. Upgrades are straightforward for anyone on a recent image:"Automatic upgrades are available from Tails 7.0 or later to 7.16."Installing fresh onto a USB stick instead of upgrading wipes the Persistent Storage, so the upgrade path is the one to take where it is available.